One of the coolest things seen in the night sky of Pagosa Springs is the bright light of the International Space Station (ISS) streaking overhead with the smaller light of the space shuttle hovering close by.

Although it may be years (or decades) before a shuttle next docks with the ISS, we can still view the ISS from Pagosa Springs during times when the station’s orbit corresponds with night time and visibility from our area. The ISS completes one orbit around the Earth approximately every 92 minutes, completing 15 1/2 orbits per 24 hours.

The ISS orbits the earth at a specific angle relative to the equator (51.6 degrees) and travels in the same direction of the Earth’s rotation from west to east. Because the Earth is also turning eastward during the orbit, the ISS does not pass over the same spot every 24 hours and thus viewing times will come and go.

NASA’s spaceflight page let’s you find ISS viewing times for a specific city.

Use NASA’s spaceflight page for a list of ISS or other manned spacecraft sightings that are viewable from Pagosa Springs. The main spaceflight page let’s users choose by state, then a specific city or coordinates in order to determine the exact viewing times for the ISS. Sighting dates are listed along with local time, duration of the fly-by, maximum elevation (how high the ISS will be in the sky), and approach and departure direction and elevation. (The chart at right is an example).

When using the chart to determine how good a sighting will be, first look for a date that has a long duration, preferably more then one minute. Next, look for the max elevation. Anything over 40 degrees is usually good. (90 degrees would be directly overhead.) The approach and departure directions are key in knowing where to look for the ISS to appear. The first time you see the space station, it may suddenly came into view and look like the white light from a very large jet, but one moving very, very fast! The ISS is brighter and larger than almost anything you’ll see in the night sky, excluding the moon.